Retractable sponson



I- 1948- I w. A. BORTNER 2,

RETRACTABLE SPONSON Filed Sept. 14, 1945 2 Sheets-Sheet l WILLIAM A.BORTNER 31, 1948- w. A. BORTNER RETRACTABLE SPONSON 2 Sheets-Sheet 2Filed Sept. 14. 1945 5.. w; w u V8 :U/ilwwfilrlwww1ylwww|bwvwi E s ,2 j-M, 1 $0 1/) n1}. 8 2 7 M. v z a m 4 I 7\ I F 2 gwum WILLIAM A BORTNERPatented Aug. 31, 1948 j sT-ATEs PATENT OFFlCEp RETRACTABLE SPONSON IWilliam A. Bortner, Baltimore, Md., assignor to -The Glenn L. MartinCompany, Middle River,

Md.,.a corporation of Maryland 14, 1945, Serial No. 616,255

4 Claims. (01. 244-102) Application September This invention relates tospray control onflying boats and moreparticularly to retractable spraycontrol strips'mounted along'the chine of. the. --hull.' I I when aflying'boat takes off from the water, it is -moved forwardly through thewater by the power of the engines and propellers until suflicient speedis obtained'so that the hull is raised from its normal waterlinefloating position until it planes onthe contoured botto'm of the hull.Asmore speed is attained, the flyingboat is supported partially byplaning on the hull bottom and partially by the aerodynamic lift of theairfoils." When thehull bottoms are formed to a contour that give a goodplaning surface they are very apt to cause aheavy spray tube-thrown off,upwardly and outwardly'from the chine of the hull. As the hull movesforwardly thisheavy spray can :cause serious interference with the tailsurfaces: of the'airplane' and therefore with some hull designs, it isnecessary to locate these stall surfaces'high off the water line. Insome instances thespray will'interfere with the engine and propellers.

The present inventionhas-for its object retractable spray "stripsextending along the chine in the side'of the hull-of a seaplane. Thesespray strips extend from a position forwardly of the leading'edge of thewing to a point under the wing along the-chine; The spray strips soarrangedare retractable into recesses in the sides of the hull andtheir'outward surfaces present a smooth continuous hull surface so thata minium of drag is offered by this structure when the seaplane is inflight. In the extended position these spray strips extend'laterally oithe chine to direct spray from the planting portions of the hulloutwardly and downwardly, thus affording additional plane area anddirectional control for the spray from the hull.

A further object of this invention is the provision for a built-inhydraulically actuated mechanism for retracting the spray strips aftertake-off; 1

A further object of this invention is the pro visionofameans to controlthe spray from the chines of the hull to direct the spray so that itwill not interfere with the functioning of the engine and propellers andcontrol surfaces on the empennage. i V

Further and other objects will become apparent from the description ofthe accompanying drawings which form a part of this disclosure and inwhich like numerals refer to like parts.

In the drawings:

Figure 1 shows a fragmentary-perspective viewv ofv a flying boatembodying the invention.

1 Figure 2 is a side sectional view through-the hull showing thespraystrip in the extended and retracted positions.

Figure 3 is a plan sectional view through the side of the hull of theflying'boat.

Figure 4 is a perspective view showing the retracting mechanism for thespray strips.

The spray strips shown in Figure 1 comprise sections I to 4 hinged alongthe chine attached to each side of the seaplane hull. In Figure 1,

the spray strip sections are shown in the open.

cr'operative position. For purposes of illustratingthe application ofthe invention, the-spray,

strips are shown under the wing and extending forward of the leadingedge of the wing,- but it should be understood that these strips can-belocated wherever objectionable spray may be encountered. The spray fromthe chine of -a seaplanehull has always been a problem and in some casesseriouslyinterferes with good design of the airplane or the take-offcharacteristics of the plane. In some seaplane designs, a gull wing isemployed to liftthe engines and propellers .up away from the'surface ofthe water-and out of the spray. But as seaplane sizes increase andgreater spray isencountered from larger hulls,

the gull wing construction presents a serious fabrication problem sothat it is desirable to use, a straight high wing extending from the top:ofv

the-hull on which the-engines and propellers are supported. The hull canbe designed to minimize the spray but it can further be controlledthrough the use of the spray strips of this invention.

Due to the long sweeping curvature of the hull along the chine, it isnecessary that the spray strip be fabricated in sections. These sectionsmay be extended into their operative position simultaneously'or as manysectionsmay be extended as observation of the spray condition indicates.are:

necessary.

Figures 2 and 3 show the relationship of the spray strips to the'hull inclosed position. The

spray'strips shown in Figures 2 to 4 for purposes of more clearlyshowingthe invention 'are views through section 4 of the spraystrip'shown in Figure l. The spray strip sections each comprisetwo-portions, section 4 shown in Figures 2 to4 comprise members 6 and lhinged by a piano hinge at 8. These members are reinforced on the insidebut offer a plane, smooth surface on the outside so that in theretracted position they maintain smooth and continuous the side of thehull. Reinforcing structures 24 and 25 are secured to the surface sheetsto render members and 1 suiilciently rigid to withstand the stressesinvolved when in the operative position. The

lower end of section 6 is hinged at 9 to the chine of the seaplane hull.The members forming sponson 4 are shown in the operative position inphantom as portion 6' and 1. The sections are capable of being movedinto a flush position shown at 6 and 1 in the side of the seaplane hull.Cavities In, II, I! and I3 formed in the side of the hull above thechine accommodate the structure of the spray strip sections I to 4.

The movement of the members forming the spray strips is accomplished bya hydraulic cylinder I 4 having fluid connections l5 and Hi to thehydraulic system. The thrust member I! of the hydraulic cylinder carriesa fitting on its outer end l8 to which is attached a bracket l9 tosupport rollers 20. These rollers are guided by roller channels 2!secured in the cavities in the side of the hull. hinged at 22 to abracket 23, also secured to fitting Hi. It will be noted in Figure 1that the adjacent ends of the spray strips or sponsons such as the endsof sponsons 3 and 4 can be connected to a single fitting I8 so that onepower unit may operate the adjacent ends of the sponson sections.sponson construction is located as shown in Figure 1 along the chine sothat spray from that portion of the hull extending forward ofthe firststep will be deflected outwardly and downwardly;

Priorto take-ofi the hull is afloat and depending upon the water linesome portion of the spray strip or some sections "may be under water. Asthe hull moves forwardly, it rises out of the water and begins to planeon the bottom surface of the hall. the seaplane gathers speed the hullrides on the forward step and from this time until take off it is mostimportant to control or direct the spray from the hull away from thecritical operating parts of the-airplane mentioned above. when it isobserved that the spray is objectionable any or all of the spray stripsmay be extended to the operative position shown in Figure 2 Portion 6shown in the extended position 6 terms a smooth continuous extension ofthe hull bottom which directs the spray outwardly and downwardly thatwould normally move upwardly around the chine and interfere with thecontrol orop-era'tion of the seaplane. As soon as the airplane leavesthe surface of the water the spray strips may be moved to the retractedposition and thereafter maintained in a closed position in the cavitiesto ofier little or no drag to the flight of the "airplane.

For the purposes of illustration, the sections of the spray strips inthe drawings are shown with a space between the adjacent edges butdepending upon the clearances and tolerances re quired, the adjacentsections of the spray strip can be as closely spaced as is practical.

It is to be understood that certain changes, alterations, modificationsand substitutions can be made without departing from the spirit andscope of the appended claims.

I claim as my invention:

l. A seaplane hull having a recess extending along the chine iorward andaft of the leading edge. of the wing, apa'nel pivoted along the chineThe upper ends of member I areadapted to move to a position extendinglaterally of said hull so that the outer surface of said panel forms acontinuation of the bottom thereof, a second panel pivoted to the outerend of said first panel, a bracket secured to the upper end of saidsecond panel, track means in said. recess and guide means [on saidbracket moving in said track means, hydraulic means secured to saidbracket to retract said hinged panels into said cavity and to extendsaid first mentioned panel into its operative position forming anextension of the hull bottom.

2. In combination in a seaplane hull having a recess extending along thechine forward and aft of the leadin edge of the wing, a panel pivotedalong the chine adapted to move to a position extending laterally of theseaplane hull forming a continuation of the bottom thereof, a secondpanel pivoted to the outer end of said first panel, a bracket secured tothe upper end of said second panel, track means in said recess androllers on said bracket moving in said track means, a hydraulic cylindersecured to said bracket to retract said hinged panels into said cavityand to extend said first mentioned panel into its operative position toform an extension of the hull bottom.

3. A seaplane hull having asha'll'ow recess formed in the side thereof,above the chine for ward and aft of the leading edge of the wing, asectional spray strip including pairs of panels placed one above theother mounted in said re cess, having the outer surface. flush with thesurface of the seaplane hull, the lower edge. of the lower panel beinghinged along the chine, the upper edge of the lower panel being hingedto the lower edge of the upper panel, the top edge of. the upper panelbeing secured to a mechanismmounted within said recess to lower eachpair of.

panels so that the lower panel is moved to a position extendinglaterally from said so that. the outer surface of said panel forms acontinua.- tion of the bottom thereof, along the chine.

4. A seaplane hull having a sectional spray strip comprising panelshingedly secured along the chine adapt-ed to be moved. to a position extending lateral-1y therefrom, the outer surface thereof forming acontinuation. of the bottom of said seaplane hull, other panels. eachhaving one edge secured to each of said first mentioned panels at theouter edge thereof, bracket members secured to the upper edge of saidsecond panel, a mechanism secured to said brackets to move the upperedge of said second panel toward said chine so that said first mentionedpanel is moved to said laterally extending position.

. WILLIAM A. BORTNER.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number I Name Date 21,158,266 Minsha'll et al.Apr. 4, 1939 2,320,574 Dornier- June 1, 1M3- FOREIGN PATENTS NumberCountry Date 842,986 France Mar. 13, 1939

